1. Technical Field
The present invention relates to a vehicle safety apparatus including an inflatable vehicle occupant restraint, and particularly relates to a vehicle safety apparatus including means for maintaining an air bag in position relative to an air bag inflator.
2. Description of the Prior Art
It is known to protect a vehicle occupant by an air bag that is inflated in the event of sudden vehicle deceleration such as occurs in a vehicle collision. The air bag restrains movement of the vehicle occupant during the collision.
The air bag is inflated by inflation fluid from an air bag inflator. The air bag is typically held in position relative to the inflator by a retaining ring which clamps the air bag against a structure such as a mounting plate. A plurality of fasteners connect the retaining ring, the air bag, the inflator, and the mounting plate. Upon actuation of the inflator, the inflation fluid flowing into the air bag exerts a force on the air bag. This force tends to pull the air bag in a direction away from the inflator. The clamping force exerted by the fasteners and the retaining ring resists movement of the air bag away from the inflator.
The use of a large number of fasteners to secure an air bag in position is disadvantageous. The fasteners add a significant amount of weight to the assembly including the retaining ring, the air bag, the inflator, and the mounting plate. It may also be difficult to align a large number of fasteners with corresponding openings in the other parts. Thus, hand assembly of the fasteners may be necessary.